Cambridge & Pearson Edexcel Past Paper Questions
Browse 35,704 questions from Cambridge O-Level & A-Level and Pearson Edexcel IGCSE & IAL exams. Click any question to practice.
A carbanion is an organic ion in which a carbon atom has a negative charge. A carbocation is an organic ion in which a carbon atom has a positive c...
What are the only structures formed when butan-2-ol is heated with concentrated H2SO4?
How many moles of hydrogen, H2, are evolved when an excess of sodium metal is added to one mole of citric acid? [Structure of citric acid: CO2H-C(O...
How many of the compounds shown will react with aqueous sodium hydroxide to form the sodium salt of a carboxylic acid? The compounds are: CH3COOCH2...
Which types of bond breakage and bond formation occur in the addition polymerisation of alkenes?
X is a particle with 18 electrons and 20 neutrons. What could be the symbol of X? 1. ³⁸₁₈Ar 2. ⁴⁰₂₀Ca²⁺ 3. ³⁹₁₉K⁺
Use of the Data Booklet is relevant to this question. Carbon and nitrogen are adjacent in the Periodic Table. Which properties do they both have? 1...
What are necessary properties of a dynamic equilibrium? 1. Equal amounts of reactants and products are present. 2. Concentrations of reactants and ...
If N2O4 gas is placed in a sealed vessel the following equilibrium is established. N2O4(g) ⇌ 2NO2(g) The forward reaction is endothermic. What happ...
Which types of bonding are present in ammonium carbonate, (NH4)2CO3? 1. ionic 2. covalent 3. co-ordinate (dative covalent)
Sulfur dioxide and sulfites are used in food preservation. Why are they used for this purpose? 1. They are reducing agents which slow down the oxid...
The organic compound X gives a precipitate when warmed with aqueous silver nitrate. This precipitate dissolves when concentrated aqueous ammonia is...
An organic compound Y, molecular formula C6H14O, may be oxidised to compound Z, molecular formula C6H12O2. What could be the structural formula of ...
Which reactions can be used to make an alcohol in the laboratory? 1. hydrolysis of a bromoalkane with NaOH(aq) 2. reduction of a ketone with NaBH4 ...
The compounds below are treated with hydrogen cyanide. Which compounds react and produce a molecule containing a chiral centre? 1. butanal 2. penta...
Which solid-line curve most accurately represents the distribution of molecular energies in a gas at 500K if the dotted-line curve represents the c...
In which reaction does hydrogen behave as an oxidising agent?
Ethanol is increasingly being used as a fuel for cars. The standard enthalpy change of formation of carbon dioxide is –393 kJ mol⁻¹. The standard e...
Two glass vessels M and N are connected by a closed valve. [Figure: Diagram showing two connected vessels M and N, separated by a valve.] M contain...
The table shows the physical properties of four substances. Which substance could be hydrogen chloride? [Table with columns: melting point /°C, ele...
Aluminium carbide, Al₄C₃, reacts readily with aqueous sodium hydroxide. The two products of the reaction are NaAlO₂ and a hydrocarbon. Water molecu...
In an experiment to calculate the enthalpy change of combustion of a fuel, 1.5g (0.0326 mol) of the fuel was used to heat 200 g of water. The tempe...
The reaction pathway diagram below illustrates the energies of the reactants, the products and the transition state of a reaction. [Figure showing ...
Methylpropan-1-ol and butan-1-ol are structural isomers. Methylpropan-1-ol has a lower boiling point. Which statement explains why the boiling poin...
Which row correctly describes the electrodes used in the electrolysis cell for the production of aluminium? [Table with columns: anode, cathode]
For which equation is the enthalpy change correctly described as an enthalpy change of formation?
Element X, in Period 3, has the following properties. • Its oxide has a giant structure. • It forms covalent bonds with chlorine. • Its oxide will ...
Which property is not associated with the element sodium?
Use of the Data Booklet is relevant to this question. Sir Humphrey Davy discovered boron, calcium, magnesium and sodium. Which of these elements ha...
Use of the Data Booklet is relevant to this question. A sample of potassium oxide, K₂O, is dissolved in 250cm³ of distilled water. 25.0cm³ of this ...
Chlorine gas reacts with cold aqueous sodium hydroxide. It can also react with hot aqueous sodium hydroxide. What are the oxidation numbers of chlo...
Total removal of the pollutant sulfur dioxide, SO₂, is difficult. The quantities emitted from furnace chimneys can be lowered by using desulfurisat...
Which oxide does not react with cold dilute sodium hydroxide to produce a salt?
Which row correctly describes the reaction between propene and bromine, Br₂(l)? [Table with columns: reaction mechanism, organic product]
Use of the Data Booklet is relevant to this question. Which compound has an M_r of 84 and will react with HBr to give a product with an M_r of 164.9?
1,1-dichloropropane reacts with aqueous sodium hydroxide in a series of steps to give propanal. CH₃CH₂CHCl₂ NaOH(aq) CH₃CH₂CHO Which term describes...
Considering only structural isomers, what is the number of alcohols of each type with the formula C₅H₁₂O? [Table with columns: primary, secondary, ...
Lactic acid, CH₃CH(OH)CO₂H, causes pain when it builds up in muscles. Which reagent reacts with both of the –OH groups in lactic acid?
In the hydrolysis of bromoethane by aqueous sodium hydroxide, what is the nature of the attacking group and of the leaving group? [Table with colum...
Corticosterone is a hormone involved in the metabolism of carbohydrates and proteins. [Figure showing the chemical structure of corticosterone.] Ho...
Methyl methylpropenoate is the monomer used to make Perspex. Which diagram correctly shows methyl methylpropenoate?
The ester CH₃CH₂CH₂CO₂CH₃ is responsible for the aroma of apples. When this ester is hydrolysed by acid in the stomach, what is the empirical formu...
Which equation correctly represents the balanced equation for the complete combustion of a hydrocarbon with the formula CₓHᵧ?
β-carotene is responsible for the orange colour of carrots. [Figure showing the chemical structure of β-carotene.] β-carotene is oxidised by hot, c...
Use of the Data Booklet is relevant to this question. Which ions contain one or more unpaired electrons? 1 Cu²⁺ 2 Mn³⁺ 3 V³⁺
Use of the Data Booklet is relevant to this question. The bond energy of the Br–O bond is 235 kJ mol⁻¹. Which reactions are exothermic? 1 OH• + HBr...
A reversible reaction is catalysed. Which statements about the effects of the catalyst on this system are correct? 1 The catalyst alters the mechan...
A student borrowed a friend's chemistry notes and copied out the notes in the box below. Which statements are correct? A gas behaves less like an i...
On being heated, hydrogen iodide breaks down more quickly than hydrogen chloride. Which statements explain this faster rate? 1 The HI bond is weake...
Which statements about calcium oxide are correct? 1 It reacts with cold water. 2 It is produced when calcium nitrate is heated. 3 It can be reduced...